319
Volume 5, Issue 10: Special Issue
(EJAR)
ISSN: 2181-2020
MPHAPP
THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL
CONFERENCE
“
MODERN PHARMACEUTICS: ACTUAL
PROBLEMS AND PROSPECTS
”
TASHKENT, OCTOBER 17, 2025
in-academy.uz
REACTION OF 4,6-DIAMINO-2-MERCAPTOPYRIMIDINE WITH ALKYL
HALIDE
Salieva G.B.
1
Otajonov S.R.
2
Karimov A.
1
Turlibekov M.
2
Kholiqov T.S.
2
1
Tashkent Pharmaceutical Institute, Tashkent city, Republic of Uzbekistan
2
National University of Uzbekistan, Tashkent city, Republic of Uzbekistan
e-mail: gulrux1431317@gmail.com
https://doi.org/10.5281/zenodo.17336473
Pyrimidine derivatives are among the most important compounds in medicinal chemistry and
pharmaceutics [1], possessing a wide range of biological activities, including antidiabetic [2], anti-
inflammatory [3], anticancer [4], antibacterial [5], antihypertensive, as well as antifungal and
antitubercular properties [6].
The aim of this work is to obtain new potential classes of biologically active compounds
through the synthesis of an S-alkylated derivative of 4,6-diamino-2-mercaptopyrimidine – 2-{(n-
pentylthio)}pyrimidine-4,6-diamine. According to the literature, such derivatives may exhibit
antibacterial, antifungal, antitumor, and insecticidal properties. Therefore, their synthesis and
subsequent evaluation of biological activity are the main objectives of this study.
Synthesis of 2-{(n-pentylthio)}pyrimidine-4,6-diamine
A two-necked round-bottom flask equipped with a reflux condenser was charged with 50 mg
(0.351 mmol) of DAMP, which was dissolved in 5.0 mL of MeOH. Then, 0.35 mL of 1.0 N NaOH
solution (0.35 mmol) was added, and the reaction mixture was stirred at room temperature for 1 h,
resulting in the formation of a yellowish compound. The obtained product was dissolved in 5.0 mL
of DMF. To this solution, 0.052 mL (density 1.215 g/mL, 0.421 mmol) of n-pentyl bromide was
added dropwise, and the mixture was stirred at 50 °C for 16 h under magnetic stirring. The reaction
progress was monitored by TLC. After completion, the mixture was cooled to room temperature, and
the solvent was removed under reduced pressure using a rotary evaporator. The crude product was
purified by extraction with chloroform and water.
Yield: 50.69 mg (68%). Product: 2-{(n-pentylthio)}pyrimidine-4,6-diamine – brown solid.
m.p.: 92–93 °C. Rf: 0.62 (system: ethyl acetate:hexane 1:2). HRMS (ESI-TOF): m/z [M+H⁺] calcd.
for C₉H₁₇N₄S⁺ = 213.1168; found = 214.1236.
Thus, the reaction of DAMP with n-pentyl bromide afforded 2-{(n-pentylthio)}pyrimidine-4,6-
diamine in 68% yield. The physical and spectral properties of the product were determined.
